I have been checking newspaper accounts from Madison and San Antonio. According to local accounts, she shot him with a .38 snubnose revolver (not an HD).
Since I purchased it from a shop in southern Wisconsin, my guess is that he sold or traded it to someone in the Madison area before he returned to Texas.
Since the letter only states that he ordered it, and he was the chief, it might even have been ordered for another officer. As the letter only mentions this one gun, I would guess that it was a personal purchase. Since the gun and box are in excellent condition considering the age, I doubt that it ever spend much time in a holster...
Inez (Heard) Weatherly, 1921-2002, was a descendant of Judge C C Dyer of Dyersburg, TN. Dyer was one of the original 300 settlers in Austin's colony, Texas.